Support for visitor.js and DIL,js functionality in scriptless scenarios

[Note: i'm not sure if this is within the scope of the alloy project, because it should be solved served-side]

### Expected Behaviour
Although it looks strange to ask for a functionality currently given by js, when js is not available, this
scenario is very usual for us. VAST (video) based advertising allows to set up URLs to be called when certain events happen (ad start, ad complete, ad clicked,etc), and we'd like to add users to segments based in those events.
Being just URLs, no script can be called at that time.What we'd expect, is some way to compose a single URL which will process the user side (visitor.js functionality), this is, checking an Adobe User Id cookie has been received, or setting it, and also, process the DMP side (DIL.js functionality), sending the signals especified in the URL, to the DMP.
Other parameters, like the GDPR consent string, etc, would be sent in that URL too.
### Actual Behaviour
Right now (and i mean, visitor.js/DIL.js), this is not possible.It's possible to send events (signals) to the DMP by mimicking the event request generated by DIL.js. But that only works for existing users, as they already have an Adobe User id cookie that it's sent along the event request.
There's no way to get a new user id and send signals to the DMP, in a single URL request.